Coefficient Of Kinetic Friction Of Sheet Metal

The value of μsis generally higher than the value of μkfor a given combination of materials.

Coefficient of kinetic friction of sheet metal.

F max frictional force n lb μ static μ s or kinetic μ k frictional coefficient f n applied normal force n lb the frictional force for dynamic friction can be expressed as. This paper presents the derivation of a first order friction model for lubricated sheet metal forming. The frictional force for static friction can be expressed as. The force of kinetic friction is μk times the normal force on a body.

Typically steel on steel dry static friction coefficient 0 8 drops to 0 4 when sliding is initiated and steel on steel lubricated static friction coefficient 0 16 drops to 0 04 when sliding is initiated. It is expressed in newtons n. Assuming purely plastic real contacts newton s law of viscosity and a square root behavior of the hydrodynamic coefficient of friction with respect to the hydrodynamic hersey parameter an analytic model is found. The kinetic friction equation can be written as.

The coefficient of kinetic friction is denoted by the greek letter mu μ with a subscript k. Coefficient of friction friction force develops between contacting surfaces of two bodies and acts to resist relative motion between the bodies. Sorry to see that you are blocking ads on the engineering toolbox. It should be noted that there can be significant differences between static friction typically higher and kinetic sliding friction.

Where f k is the force of kinetic friction μ k is the coefficient of sliding friction or kinetic friction and f n is the normal force equal to the object s weight if the problem involves a horizontal surface and no other vertical forces are acting i e f n mg where m is the object s mass and g is the acceleration due to gravity. Materials and material combinations. The coefficient of kinetic friction is the ratio f w or mg mg or simply m m. F max μ f n.

Since friction is a force the unit of the frictional force is the newton n. Hence the real contact area must be recalculated for the accurate description of friction behavior. Design resources friction design data. Based on the data you enter if the ratio m m is exactly equal to the selected μ no motion will occur.

In the micro sheet metal roll forming process the kinetic friction is significant indicating the real contact area is affected by the junction growth effect according to brizmer et al.